It is customary to provide a window in an oven door so that baking, broiling and other cooking operations within an oven can be observed. Ranges equipped with an oven self-cleaning cycle raise the temperature of the oven to temperatures which cause pyrolysis of built-up grease and grime. This results in raising the external temperatures of the oven door, and in particular the oven window, to hazardous levels. Provisions are therefore made to heavily insulate the standard oven door plug, to improve on cooling ventilation of the door and to protect with a shield the outer transparent pane in the window from thermal radiation generated in the oven operating at the higher self-cleaning temperatures. Due to this vast range of temperatures at which the oven operates, the design of the mechanism for raising and lowering the shield to and from a window covering position has to accommodate thermal expansion therein. Some mechanisms involve very complex linkage systems for raising and lowering the shield and track systems for the shield which from time to time become stuck in their operation and are usually noisy in operation. It is important to provide a lock means on the oven door to lock the oven door shut to preclude user injury while the oven is operating at the higher self-cleaning temperatures. Mechanisms are available on oven doors which raise a shield to a window covering position and lock the oven door shut on an oven. However, such mechanisms are usually complex in nature and are expensive to manufacture.
This invention provides in a windowed oven door a system which locks an oven door shut on an oven while raising a shield within the door to a window covering position in an effortless manner involving a small number of parts with the resultant reduction in manufacturing costs.